Castlevania: Bloodlines is the only Castlevania video game released on the Mega Drive/Genesis. It was developed and published by Konami, and was first released in North America, on March 17, 1994. Its Japanese title is Vampire Killer (バンパイアキラー Banpaia Kirā?). This version featured a considerable amount of violence, with the American port containing a surprising amount of blood and gore for a game of its "GA" rating. The European and Australian titles were censored and both titled Castlevania: The New Generation.
As with most early Castlevania games, players proceed through each level, defeating enemies and collecting gems (hearts in previous games) to power special weapons (in this game, the axe, boomerang, and holy water). Each stage is sectioned, and has a sub-boss battle in the middle, with a main boss battle at the end. Some items will increase the power of the characters' weapons. Some portions of the game split into different paths, depending on which character is chosen. John is able to swing past huge gaps with his whip, whereas Eric must use a different route by performing high jumps by using his spear.
Bloodlines is also noteworthy for its abundance of special effects, such as the Atlantis Shrine's water reflections, the swaying tower of Pisa, and large multi-jointed bosses. The final stage even uses effects to add challenge, such as playing upside-down or playing while the screen divides up into sections. The "Item Crash" feature (from Castlevania: Rondo of Blood) makes its return in Bloodlines.
The legendary vampire Elizabeth Bartley, Dracula's niece, suddenly appears in the 20th century. Plotting a sacrificial war in order to bring her uncle back to life, she orchestrates the beginning of World War I. Quincy Morris' son, John, and his best friend Eric Lecarde, vow to take up the fight against evil. Together they manage to prevent Dracula's full resurrection.
Unlike most Castlevania games, Bloodlines is one of the first games in the series that does not take place exclusively in Dracula's castle or even Romania. In addition to the first level (Dracula's castle in Romania), there are another five levels set in other European countries — Athens, Greece; Pisa, Italy; a weapon factory in Germany; the Palace of Versailles, in France; and the fictional Castle Proserpina in England. Despite the change in setting, however, the game still features the now-archetypal designs of Castlevania games. The player starts in the ruins of Castlevania (the first half of which is taken from the first NES game), which is a recurring theme in later titles.
This game attempts to bridge the Castlevania games with the Dracula novel written by Bram Stoker, which the series had only been loosely connected to previously; John Morris, the main player character, is said to be the son of Quincey Morris, one of the novel's heroic characters.
Additionally, the Countess Bartley is loosely based on the actual historical figure Elizabeth Báthory. The witch who resurrects her in the game's backstory is Dorottya Szentes, who in reality had connections to Báthory. (Just as the name "Bartley" in the English versions of the game is a mistransliteration of Báthory, the name "Drolta Tzuentes" is a corruption of Dorottya's name.)
The game's backstory also references the real-life death of Archduke Franz Ferdinand of Austria, suggesting that the assassination had been ordered by the Countess.
Bloodlines' story weighs heavily on Portrait of Ruin, which stars John Morris' son Jonathan as the main character. John Morris dies sometime between 1917 and 1944 as a result of his reliance on the Vampire Killer whip and the fact that it saps the energy of its non-full-blood Belmont users (John had been injured in the fight with Dracula in 1917 and his reliance on the whip never allowed him to fully recover from his wounds).
John Morris (ジョニー・モリス Jonī Morisu?) Born on December 12, 1895, in Texas, USA, is the current wielder of the Vampire Killer whip. "John Morris has been summoned by fate to slay the Countess Bartley before her diabolic plan can be fulfilled. Like all of his forefathers, he is wise in the ways of vampire slaying and is skilled with the legendary whip."
Eric Lecarde (エリック・リカード Erikku Rikādo?): Born on May 3, 1892 in Segovia, Spain, he uses the Alcarde Spear (アルカード・スピア Arukādo Supia?). "Eric Lecarde, master lanceman, has volunteered to take his friend's place in the hunt. However, he hasn't told John the real reason behind his appetite for vengeance: the Countess turned the love of his life, Gwendolyn, into a vampire." 
In 1897, the long war between humanity and Dracula came to an end, as Dracula was laid to eternal rest by Quincey Morris, a descendant of the Belmont family. Peace was restored to Europe, until the outbreak of the First World War, which transformed the continent into a dark world filled with massacre and violence. At the beginning of the war, on June 1914 at Sarajevo, the Crown Prince of Austria was assassinated. It was said that a strange beautiful woman was involved, within the shadows. It was Elizabeth Bartley (エリザベート・バートリー Erizabēto Bātorī?). In order to revive her uncle, Count Dracula, she conducted an unholy ceremony which caused the war, giving her possession of human souls from Europe.
The game itself takes place in 1917. The characters are John Morris, a descendant of the famed Belmont and Morris families who obeyed his fate to fight vampires day and night, and Eric Lecarde, whose girlfriend was transformed into a vampire when Elizabeth was revived. After Drolta Tzuentes (ドロテア・ツェンテス Dorotea Tsentesu?) resurrected Elizabeth Bartley, they traveled across Europe to conduct the resurrection of Count Dracula. John Morris and Eric Lecarde followed them. Even though the resurrection of Dracula was a success, the vampire hunters defeated him, and his allies.